The chemical industry and the petroleum industry use pipes, commonly called “pipelines” or “oil and gas pipelines” for conveying gas, water, chemical reagents, petroleum effluents, and the like, over long distances. It is well known that friction or “drag” between the fluids and the pipe or vessel wall causes substantial pressure drops as the fluids move along each wall. The drag experienced by flowing fluids in a pipeline has been directly related to the “roughness” of the inner wall of the pipeline and the roughness of interface between the liquid and gas. At the pipe wall, the roughness is caused by microscopic and/or larger pits, scratches, and other imperfections in the pipe wall which result during the manufacture of the pipe or from corrosion, abrasion, and the like during use. At the gas/liquid interface, waves are present which given the appearance of a rough surface. It has been found that the higher the value of the roughness, the more friction or drag flowing fluids will encounter in the pipeline and the greater the pressure drop of the flow. The pressure drop generated as fluid flows through a pipe is an unwelcome culprit that creates bottlenecks, interferes with fluid flow and increases production costs substantially.
To compensate for these pressure losses, pump and/or compressor stations are spaced along the pipeline to boost the pressure of the flowing fluids to a desired flow rate and to insure that the fluids will reach their destination. Due to the high costs associated with installing, maintaining, and operating such booster stations, other techniques have developed to reduce the friction or drag of fluids with pipelines as discussed below.
The current art for reduction of pressure drop in a fluid circulating in a pipe includes use of a porous inner wall within a metal pipe that allows fluid to circulate in the porous inner layer to limit the pressure drop as reported in U.S. Pat. No. 6,732,766 B2 to Charron. The Charron arrangement would substantially increase the cost and manufacture of the pipe used to convey fluids.
Rojey in U.S. Pat. No. 5,896,896 describes a pipeline wherein the pipe has a porous structure or lining into which a fluid is injected. The injected fluid is retained in the pores and is at least partially immiscible with the fluid being conveyed. The fluid retained in the pores serves as a lubricant and reduces pressure drop of fluid flowing through the pipeline. The drawback of this system is that the porous lining and injected lubricant must be adjusted to receive hydrophilic or oleophilic fluids.
U.S. Pat. No. 5,220,938 to Kley uses a friction reducing material, which includes polymeric material, liners and liners with riblets to reduce pressure drops generated by fluid flow; such materials can be an expensive addition to a pipeline.
Lowther in U.S. Pat. No. 4,958,653 describes the use of hydrocarbon drag reducers and the monitoring of pressure drop between a first point and a second point wherein the injection rate of the drag reducer is adjusted to provide the maximum flow rate with a minimum amount of drag reducer.
None of the prior art references use surfactant incorporated nano particles to reduce pressure drop and thereby increase or improve the flow rate of fluids in a pipeline. Thus, the novel product of the present invention meets a commercial need for an efficient, inexpensive product and system to reduce friction, which occurs between a fluid in a state of flow and the wall of a pipe or vessel in which it is being conveyed.